I have recently bought and tried the philips she4500 headphones and it works very well. It is a great choice for people who do not want to use basic headphones that come with the mp3 but also do not want to spend hundreds on sennheisers. The bass response is limited as it is binaural and does not fully go into the ear. It is not noise cancelling nor is it the best sound quality esp. for hip hop music with bass. The good part is that they are comfortable and you could easily forget about them. The frequency is around 20-20000. It is good for sports and excercise such as jogging because they will not fall out as easliy as ordinary apple headphones. They also have built-in volume controls and a case to put them in to prevent tangling. Another good feature is the gold plated jack. It improves longevity and good reception. The wire is pretty long and thick. The headphones do not have a microphone so it cannot be used to make calls on the iphone!